The new legislation is the first time in a decade that lawmakers from both sides of the aisle have come together to put forth serious climate policy. And like the MARKET CHOICE Act, it uses a fee to reduce pollution across the economy and includes “environmental integrity mechanisms” (EIMs) — provisions that tie a carbon fee to clear, measurable pollution reduction goals and keep us on track to meet those goals. EIMs are still a relatively new concept on the climate policy scene, but leading thinkers have begun to pay them significantly more attention, and it is clear they are emerging as a critical component of any serious carbon fee proposal: and with good reason.

A carbon fee – which sets a price per unit of pollution – prompts the economy to respond by providing powerful incentives to reduce that pollution, but it cannot guarantee the environmental result. While energy and economic modeling tools can provide critical insight into possible or likely outcomes, they cannot provide certainty over the magnitude of the impact. That’s why it is critical to include EIMs designed to provide greater assurances that a fee will deliver on its pollution reduction potential.

Momentum is building for urgent action on climate change. Last week, hundreds of protestors flooded into the Capitol calling for lawmakers to act. The recent Intergovernmental Panel on Climate Change report on the climate impacts of 1.5 degrees of warming and the U.S. National Climate Assessment paint a stark picture: the effects of warming are already here and there is no room for more delay if we are to avert disastrous impacts on human health and our economy. As this demand for action has gotten louder, so has the call for solutions that guarantee the results we need.

There is growing recognition that we need serious solutions to these pressing problems – and that means performance-based policy designed to ensure pollution reductions occur at the pace and scale the science demands. EIMs play the role of an insurance mechanism – they may never be triggered if a fee performs as expected, but provide critical safeguards in case it does not. As Rep. Ted Deutch, the author of the new bill, recognized, a price on pollution can harness the power of the market and provide a flexible cost-effective means of achieving results. But Rep. Deutch and the bill’s co-sponsors also realized that it is no longer acceptable to simply set a price and walk away, hoping the fee does the job. We also need limits on pollution, and effective mechanisms to ensure we meet our critical emissions reduction goals.

Indeed, the most straightforward way to cut pollution is to place enforceable declining limits on pollution, guaranteeing the environmental outcome, while giving businesses flexibility to determine the best way to meet it. We already have proof that those kinds of policies can help meet environmental goals faster and more cheaply than expected while growing the economy.

Regardless of the approach we take, the cornerstones of good policy design are the same: clear and measurable emission reduction goals, effective provisions to ensure they are met, and flexibility in how to meet them coupled with strong incentives to do it cheaply and efficiently. In the context of a carbon fee, that means including an EIM.

Ultimately, in order to achieve the dramatic transformational change needed to reach a 100% clean energy economy and the pollution reductions that science demands: net-zero emissions as soon as possible, a portfolio of policy approaches is needed (as others have pointed out). This means not only a limit and a price on pollution, but also investing in innovation and development of promising emerging clean energy technologies. It also means putting in place other programs that accelerate deployment of clean transportation infrastructure and promote electrification of cars and buildings. And it means encouraging states and cities to continue to lead and take action to cut pollution, pushing beyond federal requirements.

The seeds of future progress in Congress are being planted and demand is growing for durable and effective solutions that ensure environmental goals will be met. The key metric for any climate policy is environmental performance – lawmakers on both sides of the aisle are demonstrating they recognize this fundamental principle.

The California Air Resources Board’s November 6 release of 2016 greenhouse gas (GHG) emissions data from the state’s largest electricity generators and importers, fuel suppliers, and industrial facilities shows that emissions have decreased even more than anticipated. California’s emissions trends are showing what is possible with strong climate policies in place and provide hope even as new analysis projects that global emissions will increase by 2% in 2017 after a three-year plateau.

California’s emissions kept falling in 2016

The 2016 emissions report, an annual requirement under California’s regulation for the Mandatory Reporting of Greenhouse Gas Emissions (MRR), shows that emissions covered by the state’s cap-and-trade program are shrinking, and doing so at a faster pace than in prior years. Covered emissions have dropped each year that cap and trade has been in place, amounting to 31 million metric tons of carbon dioxide-equivalent (MMt CO2e) over the whole period, or 8.8% reduction relative to 2012. The drop between 2015 and 2016 accounts for over half of these cumulative reductions (16 MMt CO2e; 4.8% reduction relative to 2015). The electricity sector is responsible for the bulk of this drop: electricity importers reduced emissions about 10 MMt CO2e while in-state electricity generation facilities reduced emissions by about 7 MMt CO2e.

Some sectors’ emissions grew in 2016. Just as with global transportation emissions, California’s transportation emissions have steadily crept up in recent years, and the MRR report suggests this trend is continuing. Transportation fuel suppliers, which account for the largest share of total emissions, reported a 1.8 MMt CO2e increase in emissions covered by cap and trade since 2015. Cement plants and hydrogen plants also experienced small increases in covered emissions. One of the benefits of cap and trade, however, is that if the clean transition is occurring more slowly in one sector, other sectors will be required to reduce further to keep emissions below the cap while the whole economy catches up.

Emissions that are not covered by the cap-and-trade program dropped, from 92 MMt CO2e in 2015 to 87 MMt CO2e in 2016. While small, this represents the largest reduction in non-covered emissions since 2012 and is mostly driven by suppliers of natural gas/NGL/LPG and electricity importers. Net non-covered and covered emissions reductions resulted in a 20.5 MMt CO2e drop in total emissions from these sectors.

These results are a welcome reminder that the cap-and-trade program is working in concert with other policies to accomplish the primary objective of reducing emissions.

The California climate policies are accomplishing their emissions reductions goals

The 2016 MRR data indicate impactful reductions in GHG emissions and progress toward reaching the state’s target emissions reductions by 2020. The 2016 emissions drop is a consequence of several factors: a CARB analysis of the year’s electricity generation points to increased renewable capacity, decreased imports of electricity from coal-fired power plants, and increased in-state hydroelectric power production. To put it in perspective, the 20.5 MMt CO2e emissions reductions is equivalent to offsetting the energy use of about 2.2 million homes, or 16% of California’s households.

Emissions below the cap are a climate win, not a concern

Total covered emissions in 2016 were about 324 MMt CO2e, well below California’s 2016 cap of roughly 382 MMt. Some observers of the cap-and-trade program worry that an “oversupply” of credits will result in reduced revenue for the state and lesser profits for traders on the secondary market. This concern was especially pronounced when secondary market prices dipped below the price floor in 2016 and 2017.

Importantly, oversupply of allowances is not a bad thing for the climate. As Frank Wolak, an energy economist at Stanford, points out, oversupply may be a sign of an innovative economy in which pollution reductions are easier to achieve than anticipated. Furthermore, having emissions below the cap represents earlier than anticipated reductions which is a win for the atmosphere. Warming is caused by the cumulative emissions that are present in the atmosphere so earlier reductions mean gases are not present in the atmosphere for at least the period over which emissions are delayed.

While market stability is a valid concern, the design of the program has built-in features to prevent market disruptions. Furthermore, the California legislature’s recent two-thirds majority vote to extend the cap-and-trade program through 2030 provides long-term regulatory certainty. Both the May and August auctions were completely sold out suggesting that the extension has succeeded in stabilizing demand.

These results are a welcome reminder that the cap-and-trade program is working in concert with other policies to accomplish the primary objective of reducing emissions, and that we’re doing it cheaply is an added bonus. Early reductions at a low cost can lead to sustained or even improved ambition as California implements its world-leading climate targets.

As California closes its fifth year of cap and trade, it should be with a sense of accomplishment and optimism for the future of the state’s emissions.

More than 200 world leaders met over the last few days at the United Nations’ Annual Climate Change Conference in Bonn to discuss how to fill in the details of individual countries’ pledges of the Paris agreement. And while the United States has clearly ceded its leadership role to China, Germany, France, Canada and others, there are clear signs that adopting an ambitious climate policy is smart for long-term economic prosperity.

Economists across the political spectrum agree that the market alone will not solve climate change, because carbon pollution is still largely unpriced. From an ideal point of view, the optimal climate policy would be a global carbon price. If an appropriate and sufficiently robust global carbon price existed, with clear declining limits on pollution, no other climate policy would be needed.

Unfortunately, such a carbon policy does not currently exist. So, in the absence of such a global pricing regime, what kind of climate policy is cost-effective? Each individual climate policy can be judged on its merits, and most typically show large economic gains, as the benefits of avoiding climate change far outweigh the costs.

Ambitious climate policy passes a benefit-cost test by using the Social Cost of Carbon

To understand the benefit of climate policy, we first need a sense on the magnitude of the climate damages that can be avoided. The current economic consensus view quantifies the social cost of carbon – that is the damage from emitting one ton of CO2 – at $42 per metric ton of CO2 emissions in 2007 U.S. Dollars based on work by the U.S. Government’s Interagency Working Group on Social Cost of Greenhouse Gases.

But what about the cost of climate policy? For many, the potential cost of enacting ambitious climate policy has become a powerful argument against taking any sort of action. So how can we tell if enacting climate policy is cost-effective? A first pass is to subject individual climate policy proposals to benefit-cost analyses that weigh the cost of the specific policy against the avoided climate damages using the social cost of carbon. For example, if the climate mitigation component of a renewable energy proposal costs less than the social cost of carbon, then the policy is good economics.

On the flip side, failing to pass a benefit-cost test does not necessarily imply that a policy is not cost-effective. The social cost of carbon still only captures some of the damages, and future revisions will in all likelihood correct it upwards. Additionally, a policy might lead to important co-benefits beyond climate policy such as reductions in criteria pollutants that have negative effects on human health and the environment.

The Clean Power Plan can serve as a good example to illustrate the argument. Using benefit-cost analysis based on the social cost of carbon, the EPA determined that the Clean Power Plan is a worthwhile investment, with net gains totaling billions of dollars. This is the case even when ignoring any non-climate co-benefits, and when using the lower consensus estimate for the social cost of carbon. Relying instead on the newly available climate impact estimates adds several billion dollars to the net benefits.

Climate policy can go hand in hand with economic prosperity

Moreover, the evidence suggests that – contrary to what some claim – we can implement climate policy while growing the economy. While there can be small adjustment costs, climate policy also leads to lead to new opportunities and innovation. Patenting in clean technologies, for instance, is as vibrant as in biotech, translating into additional growth benefits for the economy as a whole.

Uncertainty makes acting now even more compelling

While there is uncertainty as to just how much CO2 levels in the atmosphere will rise, we know it will be more than ever before encountered by modern humans. And, we already know the economic impacts will be bad. The devastation from hurricanes Harvey, Irma and Maria—made worse by the impacts of a warming climate—will cost communities, taxpayers and insurance companies billions.

But things could turn out much worse. Theoretically, catastrophic climate damages could be so highas to dominate any benefit-cost analysis. This as of yet unpriced uncertainty is a compelling reason to act, not to wait. How to quantify uncertainty with precision is still at the frontier of climate economics. A recent working paper at the NBER calibrates a climate-economy model to financial risk attitudes. The authors find that taking the uncertainty in climate impacts seriously will increase the social cost of carbon even more.

The economic case for ambitious climate action is clear. With the right policies, the benefits of avoiding climate change far outweigh the costs. And in the absence of a price on carbon, the only question is: what are the right climate policy instruments? As EDF has long argued, political debates in climate policy must not be over the if, but the how.

At a recent EDF board meeting, Geoffrey Heal talked about the economic values that ecosystem services provide for our economic well-being. His presentation included a number of case studies, including the New York City Department of Environmental Protection’s financial support for farmers in the Catskills to farm in ways that protect the city’s water quality. The key to the business model: farmers benefit by getting financial support from the City of New York, and the city avoids having to go through a costly filtration system to physically remove impurities or contaminants in a series of filters. The city water supply does undergo UV decontamination.

Last week, the staff of EDF’s Office of the Chief Economist decided to see for ourselves how this works in practice. We visited with Gibson Durnford, the East of the Hudson Agricultural Coordinator of the Watershed Agricultural Council, based in Yorktown Heights, New York. A non-profit organization led by local farmers, it started in 1993 to lead and administer the program.

Incentives for farmers and the City are aligned

Gibson explained that customers in New York City consume 1 billion gallons of water a day, which is supplied from the West and East Hudson systems. There is one and a half years of water in storage (550 billion gallons).

If farmers did not protect the Delaware and Catskill water sheds, the City would have to make a an estimated capital investment of $8-10 billion in water filtration plants and spend an additional $100 million annually to operate them. Phosphate is a particular problem, and the city would also have to deal with sediment running off the farms into the water supply system.

For farmers, payments for eco-services compensate and empower private landowners to be surface-water stewards of New York City’s drinking water. Whole farm management plans are agreed with farmers, incorporating best management practices that both support sustainable farming and protect water quality; concentrated manure sources like slurry pits or storage piles are a greater concern than waste in the fields. If fields are well-vegetated with grass, the plants will take up nutrients; the vegetation slows water flow and also makes the soil more porous and increases absorption.

Farmers are provided with investment funds for purposes which include drainage, roading, manure pads, and sward management; conservation easements are purchased (a percentage of market value) which simultaneously lets the farmer retain ownership of the land, releases capital for the owner while ensuring that the land remains available for farming and forestry; the forest program helps farmers with erosion control, sustainable harvesting, and planting on the banks of tributaries.

Conservation in action at an Alpaca farm We visited Leda Bloomberg and Steve Cole’s Faraway Farm, where they raise Alpaca sheep for their wool. The Watershed Agricultural Council supported the installation of a manure pad, and of a rocky channel along the roadway had drains it to collect the water running off the field and divert it away for infiltration into the soil. Leda and Steve indicated that they had benefited greatly from the advice and support of the Watershed Council. The council is “on the side of the farmers” and is proactive in finding new and better ways to conserve and better their well-being.

The economist Ronald Coase won the Nobel Prize, in part for theorizing (without evidence) that those who pollute could negotiate a solution with those who would benefit from pollution reduction. We were honored and delighted to see his theory being acted upon to such great positive effect for both farmers upstate and the water consumers in New York City. As we left, we had only one question: Doesn’t such a great idea deserve to be replicated?

The Trump Administration is attempting to justify the rollback of crucial environmental and health protections by vastly undervaluing the costs of climate change.

The latest safeguards under attack are the Clean Power Plan, the nation’s first-ever limits on carbon pollution from existing power plants, and the Bureau of Land Management’s vital standards to reduce wasted natural gas from oil and gas facilities on public and tribal lands. They would have health, environmental, and economic benefits worth an estimated billions of dollars annually. But you wouldn’t know it from reading the Administration’s recently revised documents – because of a series of deceptive accounting tricks, including efforts aimed at obscuring the benefits of reducing carbon pollution.

The Trump Administration has used discredited methods to eviscerate the social cost of carbon — an estimate of the costs that carbon pollution inflicts on the public, represented as the dollar value of the total damages from emitting one ton of carbon dioxide into the earth’s atmosphere.

The social cost of carbon is a tool that helps ensure that policymakers consider the health, environmental and economic benefits of avoiding extreme weather, rising temperatures and intensifying smog when they make decisions that affect climate pollution.

Climate change harms businesses, families, governments and taxpayers through rising health care costs, destruction of property, increased food prices and more — so it’s common sense that we should properly account for the value of avoiding these harmful outcomes. But the Trump Administration has systematically undermined and attacked the well-established science of climate change – including the social cost of carbon, which has had a target on its back for a while now.

The most up-to-date estimates of the social costs of carbon were developed by an Interagency Working Group (IWG) of experts from a dozen federal agencies. They were developed through a transparent and rigorous process based on the latest peer-reviewed science and economics, and with input from the public and the National Academy of Sciences.

But in March, President Trump cast aside the results of this thorough and consultative process. He issued an executive order aimed at discrediting the IWG estimates, withdrawing them as government policy, and directing federal agencies to pick their own metric.

The executive order leaves federal agencies to fend for themselves without specific guidance, opens the door to extensive legal challenges, and effectively sets up agencies to cook the books to serve the Administration’s goals.

That’s exactly what EPA Administrator Scott Pruitt and Department of the Interior Secretary Ryan Zinke just did – releasing benefit-cost analyses that massively undervalue the costs of carbon pollution, radically reducing the estimates by up to 97 percent.

The Trump Administration would have us believe that the costs of carbon pollution are near zero. The Administration’s new estimates are only a couple dollars per ton of carbon dioxide – about as much as a cup of coffee or a bus ticket.

Even the IWG estimates – roughly $50 per ton of carbon dioxide based on year 2020 emissions – are almost certainly a conservative lower bound since they do not yet reflect many different types of climate impacts.

A closer look at the Administration’s deceptive math

There are two major flaws in the Administration’s drastically reduced estimates, both of which fly in the face of established science and economic principles in service of obscuring the very real benefits of climate action.

First, the reduced estimates ignore that carbon emissions are a global pollutant, so they omit important categories of climate change impacts on the United States.

Second, they shortchange the harm to our children and future generations from climate change.

The so-called “domestic-only” estimate

Since the impacts of carbon pollution are felt globally regardless of where the emissions come from, leading researchers and the IWG have appropriately focused on accounting for that full global impact.

In contrast, the Administration’s revised estimates claim to consider “domestic-only” impacts to the United States. But that title is a misnomer – the Administration’s flawed approach ignores important categories of impacts that affect the American public. Climate impacts beyond our borders have costly repercussions for U.S. citizens in the form of changing global migration patterns, economic and political destabilization, and other “spillover” effects.

The National Academy of Sciences specifically rejected the approach the Administration is taking in a report released earlier this year, concluding that:

[C]limate damages to the United States cannot be accurately characterized without accounting for consequences outside U.S. borders.

[The] United States benefits tremendously if other countries set policy based on global rather than local effects.

They also point out that the use of a global estimate can encourage reciprocal climate action elsewhere. For instance, the Canadian government incorporated the U.S. IWG value in its own policy analysis.

Undervaluing the impacts on children and future generations

The Administration’s estimates also use a sharply lower value for the benefits that today’s carbon reductions provide to children and future generations. Again, this is in direct conflict with the weight of expert opinion that supports valuing these impacts even more than we did before the Trump Administration.

The Administration’s estimates “discount” future impacts at 7 percent – a rate significantly higher than the 3 percent central rate of the IWG, and one that is wholly unsupported by the economics literature when it comes to the long-lived intergenerational effects of carbon pollution.

Practically speaking, the use of such a high discount rate means that the effects of our actions on future generations are largely unaccounted for in the new analysis.

In other words, the Administration’s estimates reveal just how little they value protecting American children and generations to come.

The social cost of carbon has profound influence on our policy process and embodies the very real costs of climate change that communities around the country are already feeling.

The Administration’s distortion of these values is illustrative of a frequent strategy of theirs – twisting the facts to validate their desired outcome, and in the process sowing doubt around the overwhelming scientific consensus on climate change.

Unfortunately, while the math the Administration is using is warped, the costs of climate change are still very real – and the American public is footing the bill.